Electric power jack



J. M. CRUM.

ELECTRIC POWER JACK.

APPLICATION FILED 001 20. 1921.

1,423,83%. Patented July 25, 1922.

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QJ.M.CRUM.

ELECTRIC POWER LACK.

APPLICATION FILED 00L20.1921.

1 ,428,88%, Patented. July 25, 1922.

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ELECTRIC rowan JACK.

T 0 all whom it may concern:

Be it known that JOHN M. ORUM, a citizen of the United States, residing at Johnstown, in the county of Cambria and State of Pennsylvania, has inventedcertain new and useful Improvements in Electric Power Jacks, of which-the following is a specifica- This invention relatesto improvements in lifting jacks, and more especially to electrically operated power jacks.

An object of the invention is to provide a suitable electrically operated power jack' which will be highly e fiicient in use and inexpensive to manufacture.

Another object of the invention is to provide an electric power ack which will be so constructed as to prevent any injury to the operating mechanism or motor, should the load slip or any part of the jack fail to function properly.

A further object of the invention is to provide a suitable jack which will be oper-' ated by an electric motor or generator of any size and using any kind of current, either high or low voltage.

Al still further object of the invention" is r to proyide a suitable electric power jack,

which will be provided with means for operating the motor in either direction to raise or lower the jack screw and means to stop the motor at will, and also a safety catch to prevent the jack screw from slipping when it is in the position desired.

Other objects will appear as the description proceeds.

In the accompanying drawings which constitute a part of my application,

Figure 1.is a side elevation of my improved electric power jack;

Figure 2 is a vertical sectional view through the said jack;

Figure 3 is a rearview of the jack, show ing the safety handles, 'and lock for the jack screw;

Figure 4: is a plan view of my improved electric power jack, and

Figure 5 is a detail view of the safety lock or catch for preventingthe slipping of the jack screw.

Like characters of reference are used throughout the following specification to designate corresponding parts.

The body 1 of the jack is provided with the spaced vertically extending flanges or Wing portions 2, which are formed integral Specification of Letters Patent. Patentgd J 11y 25 1922.

Application filed October 20, 1921'. Serial No. 509,094.

with the body or jack housing 1. The lower portions of the flanges 52 extend out a considerable distance beyond the upper portions, as at 3, to provideadditional space for the housing of the motor or generator 4. Th1s motor or generator 4, may be made in any desired size and horse power, and used with any kind of electric current, either alfor operating the motor in one direction,

stopping and reversing the motor, respectively. It will be understood that these switch buttons may be replaced by any suitable or desired type of switches, as will be found most convenient and practicable in manufacturing the same. The switches extend up through the housing plate 5, as do also the electric feed wires 9, which in use will be connected to the source of current supply.

Within the body 1 of the jack, is the Central well 10 for the reception of the screw threaded jack screw 11, which is adapted to operate therein. On the outer end of the jack screw 11 is the cap member or work rest 12, which is made preferably round, but may be made in any desired shape or form to more readily hold the load to be lifted. The upper surface of the cap member 12 may begrooved as at 13 to prevent the load from slipping, or may be roughened in any manner desired.

An annular groove 14 is formed in the upper surface of the body 1, in which is placed the ball bearings 15. An internally screw threaded nut or operating gear fol lower 16 is threaded upon the jack screw 11, and is prpvided with an annular groove 17, similar to the groove 14, tocomplete the race or housing for the ball bearings 15. It will be understood that the nut 16 rests upon the ball bearings 15, and rotates thereon. Oil passages 18 are formed in the nut 16 to permit of the lubricating ofthe ball bearings 15. The periphery of the cap nut 16 is provided with the beveled teeth 19, thereby forming a beveled gear as well as an operating nut. Diametrically opposite each other are the vertically extending channels or slots 41. The lower end of the jack screw 11 iscut away to receive the ring 42 which extends fiush with the surface of the screw. removable pin 43 passes through the ring 42 and screw 11, and extends out beyond the opposite sides of the ring into the. slots 41, to prevent the screw from rotating. A screw plug 44 is removably secured in the bottom of the well 10, to permit cleaning, etc.

Cast one above the other and intermediate of the wing portions 2 on the flat side 20 of the body 1, are the bearing posts or studs 21 and 22. These studs are formed integral with the body 1, and serve as an axle or support for the large gear wheel 23 and the smaller gear wheel 24, which intermesh one with the'other. The gear wheel 23 is provided with a bevel gear surface 25 and also the spur gear surface '26. The bevel gear 25 meshes with the bevel gear 19 on the nut 16, and the spur gearing 26 meshes with the spur gearing 27 on the small gear wheel 24. A considerably smaller spur gear 28 is carried by. the motor shaft 29, andintermeshes with the spur gearing 27 on the wheel 24. Thus it will be seen that when the motor is started, the ack screw will be raised or lowered according to the direction the motor,

is running. All ofthe gearing and operating nut will be mounted onball bearings,

and therefore will have little to no friction to hinder the operation of the jack screw.

Since most of the gearing and motor are encased within the wingportions 2 and housing plate 5, there will be no chance of any dirt getting into the operating mechanism, or the mechanism becoming injured from any object striking the jack. Cast integral with the body 1- of the jack, and at only one side thereof, are the pair of ears or bearing .wings 30, which has the vertical bearing rod 31 mounted there-between. Pivoted on the rod 31 is the safety locking lever 32, which has formed thereon a section of an internal spur gear 33, which is adapted to be swung into engagement with the spur gear surface 26 of the gear 23,- to lock the jack from slipping, when the desired adjustment is had. The adjacent wing portion 2 is provided with a small opening or passage 34, through which the gear section 33 may pass when being placed in engagement with spur gear surface 26. A flange or annular extension 35 is cast integral with the bottom portion of the body 1, to give an additional supporting surface to the jack.

Cast integral with the upper portion of the body 1 of the jack and at opposite sides thereof,'are the spaced vertically extending ears 36, which are connected together by means of the bolts 37. Mounted on these bolts 37, are the handles 38, which are provided with the spaced arms 39, the same being formed integral with the handles, to prevent the handles from lifting or swingingv up further than a horizontal position, which would be possible if these arms did not contact or engage with thewall of the body 1. Thus it will be seen that it will be impossible for the person or persons carryingthe jack to pinch or injure their fingers.

Detachably mounted on.the bolts 37 is a balehandle 40, which will permit of the carrying of the jack-on a pole, should the weight of the jack be too great for two 'persons to carry by the handles. handle may be detached at will, or may be done away with in the smaller sizes of jacks.

This bale I It will be understood that I do not limit myself to the specific form of construction, as many. minor changes in detail of construction may be resorted to without departure from the spirit of the invention.

It will further be understood that as many cogs as necessary may be used on difierent sizes of jacks to reduce to the proper speed. The gear cover or housing plate 5 may also be made in two parts if desired and held in position with stud bolts or in any desired manner, so that more ready access may be had to repair the gearing or motor if necessary.

Having thus described my invention what I claim as new and" desire to secure by Letters Patent of the United States is:

1. An electric power jack comprising a body portion, spaced laterally extending wing portions formed integral therewith, a jack screw operable in. said body, a nut or follower carried by said screw means for preventing said screw from rotating, an electric =motor positioned between said spaced wing portions; and means connecting said.

motor with said nut for operating thejack.

2. An electric power jack comprising a body portion spaced. laterally extending wings formed integral therewith, a jack screw operable in said body, a nut or follower carried by said screw and rotatably mounted on said-body means for preventing said screw from rotating,,a motor positioned between said laterally extending wings, a train of gearing connecting said motor with said nut, and means for operating the motor in forward or reverse direction, or stopping the same.-

3. An electric power jack-comprising a body portion, spaced laterally extending wings formed integral therewith, a jack screw operable in said body, a nut or follower carried by said screw means for pre venting said screw from rotating, an electric motor or generator positioned 'between said laterally extending wings,,a-train of gearing connecting said motor and nut, and a gear cover or housing plate detachably secured to said /wing o'rtions for housing the operatmg mechanism,

gear, a combined bevel and spur gear mount ed at the side of said jack body and intermeshing with the bevel gearing on the said nut, a. smaller gear mounted below said combined .bevel and spur gear and meshin therewith, a motor mounted between sai wing portions, and a spur gear carried by said motor and intermeshing with said last mentioned gear, whereby the jackvscrew may be raised or lowered as desired.

5. An electricpower jack comprising a body portion, spaced laterally extending wings formed integral therewith, a reversible motor positioned between said wings, a jack screw operable in said body, a nut carried by said screw, said nut being positioned adjacent the top of said body and mounted upon ball bearings said body being provided with oppositely disposed. vertically extending channels, detachable means carried by sald screw adaptedto slide in said channels to prevent said screw from rotating, a plurality of stub axles or shafts formed integral with said body, intermeshing gears mounted. thereon, one of said gears meshing with said nut and the other meshing with a relatively smaller gear mounted upon the motor shaft, a cover plate detachably connected to said wings, and motor control switches, passing through said cover, for operating the motor in the desired direction or for stopping the sa ne.

6. An electric power jack comp-rising a body portion, a jack screw operable therein, an electric motor encased within said body, means connected with said motor for operating said screw means for preventing said screw from rotating, and means locking the screw from accidental movement.

In testimony whereof I aflix si nature.

JOHNli C UM. 

